diff --git a/sample-pushnotifications-java/app/build.gradle b/sample-pushnotifications-java/app/build.gradle
index 095fb677c..346614bb3 100644
--- a/sample-pushnotifications-java/app/build.gradle
+++ b/sample-pushnotifications-java/app/build.gradle
@@ -1,41 +1,34 @@
 buildscript {
     repositories {
         google()
-        jcenter()
-        maven { url 'https://maven.fabric.io/public' }
-    }
-
-    dependencies {
-        classpath "io.fabric.tools:gradle:$fabricToolsVersion"
+        mavenCentral()
     }
 }
 
 apply plugin: 'com.android.application'
-apply plugin: 'io.fabric'
 
 repositories {
     google()
-    jcenter()
+    mavenCentral()
     maven {
         url "https://github.com/QuickBlox/quickblox-android-sdk-releases/raw/master/"
     }
-    maven { url 'https://maven.fabric.io/public' }
-    flatDir { dirs 'libs' }
 }
 
+
 android {
     def versionQACode = 1
 
-    compileSdkVersion 28
-    buildToolsVersion "28.0.3"
+    compileSdkVersion 31
+    buildToolsVersion "31.0.0"
     flavorDimensions dimensionDefault
 
     defaultConfig {
         applicationId "com.quickblox.sample.pushnotifications.java"
-        minSdkVersion 14
-        targetSdkVersion 28
-        versionCode 401000
-        versionName '4.0.1-java'
+        minSdkVersion 21
+        targetSdkVersion 31
+        versionCode 402000
+        versionName '4.0.2-java'
         multiDexEnabled true
     }
 
@@ -59,12 +52,14 @@ android {
             minifyEnabled false
             shrinkResources false
             proguardFile 'proguard-rules.pro'
-            zipAlignEnabled false
             resValue "string", "versionName", "QuickBlox Push Notifications Java\nBuild version " + defaultConfig.getVersionName()
         }
 
         release {
             signingConfig signingConfigs.debug
+            minifyEnabled true
+            shrinkResources true
+            proguardFile 'proguard-rules.pro'
             resValue "string", "versionName", "QuickBlox Push Notifications Java\nBuild version " + defaultConfig.getVersionName()
         }
     }
@@ -88,9 +83,6 @@ dependencies {
     implementation "com.google.firebase:firebase-core:$firebaseCoreVersion"
     implementation("com.google.android.material:material:$materialVersion")
     implementation "com.github.johnkil.android-robototextview:robototextview:$robotoTextViewVersion"
-    implementation("com.crashlytics.sdk.android:crashlytics:$crashlyticsVersion@aar") {
-        transitive = true
-    }
 }
 
 apply from: "../artifacts.gradle"
diff --git a/sample-pushnotifications-java/app/google-services.json b/sample-pushnotifications-java/app/google-services.json
index 542e3ac38..1bd4a8ca8 100644
--- a/sample-pushnotifications-java/app/google-services.json
+++ b/sample-pushnotifications-java/app/google-services.json
@@ -1,154 +1,29 @@
 {
   "project_info": {
-    "project_number": "247738611464",
-    "firebase_url": "https://qb-prod-samples.firebaseio.com",
-    "project_id": "qb-prod-samples",
-    "storage_bucket": "qb-prod-samples.appspot.com"
+    "project_number": "Put here your value",
+    "firebase_url": "https://qb-samples.firebaseio.com",
+    "project_id": "qb-samples",
+    "storage_bucket": "qb-samples.appspot.com"
   },
   "client": [
     {
       "client_info": {
-        "mobilesdk_app_id": "1:247738611464:android:beb270faa2c3a789",
-        "android_client_info": {
-          "package_name": "com.quickblox.sample.chat.java"
-        }
-      },
-      "oauth_client": [],
-      "api_key": [
-        {
-          "current_key": "AIzaSyBFXAfVr6kkFJdDNOm8U-c7iju0qIUkc_A"
-        }
-      ],
-      "services": {
-        "appinvite_service": {
-          "other_platform_oauth_client": [
-            {
-              "client_id": "247738611464-v2nvd29bmqum7niosnfuh28oq3beh9f6.apps.googleusercontent.com",
-              "client_type": 3
-            }
-          ]
-        }
-      }
-    },
-    {
-      "client_info": {
-        "mobilesdk_app_id": "1:247738611464:android:1cdc72e9ffd29448",
-        "android_client_info": {
-          "package_name": "com.quickblox.sample.chat.kotlin"
-        }
-      },
-      "oauth_client": [],
-      "api_key": [
-        {
-          "current_key": "AIzaSyBFXAfVr6kkFJdDNOm8U-c7iju0qIUkc_A"
-        }
-      ],
-      "services": {
-        "appinvite_service": {
-          "other_platform_oauth_client": [
-            {
-              "client_id": "247738611464-v2nvd29bmqum7niosnfuh28oq3beh9f6.apps.googleusercontent.com",
-              "client_type": 3
-            }
-          ]
-        }
-      }
-    },
-    {
-      "client_info": {
-        "mobilesdk_app_id": "1:247738611464:android:06cb0de4c719ad84",
+        "mobilesdk_app_id": "Put here your value",
         "android_client_info": {
           "package_name": "com.quickblox.sample.pushnotifications.java"
         }
       },
-      "oauth_client": [],
-      "api_key": [
+      "oauth_client": [
         {
-          "current_key": "AIzaSyBFXAfVr6kkFJdDNOm8U-c7iju0qIUkc_A"
+          "client_id": "Put here your value",
+          "client_type": 3
         }
       ],
-      "services": {
-        "appinvite_service": {
-          "other_platform_oauth_client": [
-            {
-              "client_id": "247738611464-v2nvd29bmqum7niosnfuh28oq3beh9f6.apps.googleusercontent.com",
-              "client_type": 3
-            }
-          ]
-        }
-      }
-    },
-    {
-      "client_info": {
-        "mobilesdk_app_id": "1:247738611464:android:c2749661061637f0",
-        "android_client_info": {
-          "package_name": "com.quickblox.sample.pushnotifications.kotlin"
-        }
-      },
-      "oauth_client": [],
-      "api_key": [
-        {
-          "current_key": "AIzaSyBFXAfVr6kkFJdDNOm8U-c7iju0qIUkc_A"
-        }
-      ],
-      "services": {
-        "appinvite_service": {
-          "other_platform_oauth_client": [
-            {
-              "client_id": "247738611464-v2nvd29bmqum7niosnfuh28oq3beh9f6.apps.googleusercontent.com",
-              "client_type": 3
-            }
-          ]
-        }
-      }
-    },
-    {
-      "client_info": {
-        "mobilesdk_app_id": "1:247738611464:android:99e5b55a490c901c",
-        "android_client_info": {
-          "package_name": "com.quickblox.sample.videochat.java"
-        }
-      },
-      "oauth_client": [],
       "api_key": [
         {
-          "current_key": "AIzaSyBFXAfVr6kkFJdDNOm8U-c7iju0qIUkc_A"
-        }
-      ],
-      "services": {
-        "appinvite_service": {
-          "other_platform_oauth_client": [
-            {
-              "client_id": "247738611464-v2nvd29bmqum7niosnfuh28oq3beh9f6.apps.googleusercontent.com",
-              "client_type": 3
-            }
-          ]
-        }
-      }
-    },
-    {
-      "client_info": {
-        "mobilesdk_app_id": "1:247738611464:android:ac22e0d1b3a3e86b",
-        "android_client_info": {
-          "package_name": "com.quickblox.sample.videochat.kotlin"
-        }
-      },
-      "oauth_client": [],
-      "api_key": [
-        {
-          "current_key": "AIzaSyBFXAfVr6kkFJdDNOm8U-c7iju0qIUkc_A"
-        }
-      ],
-      "services": {
-        "appinvite_service": {
-          "other_platform_oauth_client": [
-            {
-              "client_id": "247738611464-v2nvd29bmqum7niosnfuh28oq3beh9f6.apps.googleusercontent.com",
-              "client_type": 3
-            }
-          ]
+          "current_key": "Put here your value"
         }
-      }
+      ]
     }
   ],
   "configuration_version": "1"
diff --git a/sample-pushnotifications-java/app/proguard-rules.pro b/sample-pushnotifications-java/app/proguard-rules.pro
index f1dd7da4b..be6afe8c2 100755
--- a/sample-pushnotifications-java/app/proguard-rules.pro
+++ b/sample-pushnotifications-java/app/proguard-rules.pro
@@ -1,13 +1,11 @@
 # Add project specific ProGuard rules here.
 # By default, the flags in this file are appended to flags specified
-# in /home/tereha/Android/sdk/tools/proguard/proguard-android.txt
+
 # You can edit the include path and order by changing the proguardFiles
 # directive in build.gradle.
 #
 # For more details, see
-#   http://developer.android.com/guide/developing/tools/proguard.html
-
-# Add any project specific keep options here:
+# http://developer.android.com/guide/developing/tools/proguard.html
 
 # If your project uses WebView with JS, uncomment the following
 # and specify the fully qualified class name to the JavaScript interface
@@ -23,48 +21,16 @@
 ##---------------Begin: proguard configuration for Gson  ----------
 # Gson uses generic type information stored in a class file when working with fields. Proguard
 # removes such information by default, so configure it to keep all of it.
+-keepattributes EnclosingMethod
+-keepattributes InnerClasses
 -keepattributes Signature
+-keepattributes Exceptions
 
 # For using GSON @Expose annotation
 -keepattributes *Annotation*
 
-# Gson specific classes
--keep class sun.misc.Unsafe { *; }
-#-keep class com.google.gson.stream.** { *; }
-
-# Application classes that will be serialized/deserialized over Gson
- -keep class com.quickblox.core.account.model.** { *; }
-
-
-##---------------End: proguard configuration for Gson  ----------
-#quickblox sample chat
-
--keep class com.quickblox.auth.parsers.** { *; }
--keep class com.quickblox.auth.model.** { *; }
--keep class com.quickblox.core.parser.** { *; }
--keep class com.quickblox.core.model.** { *; }
--keep class com.quickblox.core.server.** { *; }
--keep class com.quickblox.core.rest.** { *; }
--keep class com.quickblox.core.error.** { *; }
--keep class com.quickblox.core.Query { *; }
-
--keep class com.quickblox.users.parsers.** { *; }
--keep class com.quickblox.users.model.** { *; }
-
--keep class com.quickblox.chat.parser.** { *; }
--keep class com.quickblox.chat.model.** { *; }
-
--keep class com.quickblox.messages.parsers.** { *; }
--keep class com.quickblox.messages.model.** { *; }
-
--keep class com.quickblox.content.parsers.** { *; }
--keep class com.quickblox.content.model.** { *; }
-
--keep class org.jivesoftware.** { *; }
-
-#sample chat
--keep class android.support.v7.** { *; }
--keep class com.bumptech.** { *; }
+#quickblox sdk
+-keep class com.quickblox.** { *; }
 
--dontwarn org.jivesoftware.smackx.**
--dontwarn android.support.v4.app.**
\ No newline at end of file
+#google gms
+-keep class com.google.android.gms.** { *; }
\ No newline at end of file
diff --git a/sample-pushnotifications-java/app/src/main/AndroidManifest.xml b/sample-pushnotifications-java/app/src/main/AndroidManifest.xml
index fff792ac7..204154fea 100644
--- a/sample-pushnotifications-java/app/src/main/AndroidManifest.xml
+++ b/sample-pushnotifications-java/app/src/main/AndroidManifest.xml
@@ -19,6 +19,7 @@
 
         <activity
             android:name=".activities.SplashActivity"
+            android:exported="true"
             android:screenOrientation="portrait">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
@@ -49,13 +50,17 @@
             </intent-filter>
         </service>
 
-        <service android:name="com.quickblox.messages.services.fcm.QBFcmPushListenerService">
+        <service
+            android:name="com.quickblox.messages.services.fcm.QBFcmPushListenerService"
+            android:exported="false">
             <intent-filter>
                 <action android:name="com.google.firebase.MESSAGING_EVENT" />
             </intent-filter>
         </service>
 
-        <service android:name="com.quickblox.messages.services.fcm.QBFcmPushInstanceIDService">
+        <service
+            android:name="com.quickblox.messages.services.fcm.QBFcmPushInstanceIDService"
+            android:exported="false">
             <intent-filter>
                 <action android:name="com.google.firebase.INSTANCE_ID_EVENT" />
             </intent-filter>
diff --git a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/App.java b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/App.java
index 82fc9f168..a53dd4974 100644
--- a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/App.java
+++ b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/App.java
@@ -4,7 +4,6 @@
 import android.text.TextUtils;
 import android.util.Log;
 
-import com.crashlytics.android.Crashlytics;
 import com.google.android.gms.common.GoogleApiAvailability;
 import com.quickblox.auth.session.QBSession;
 import com.quickblox.auth.session.QBSessionManager;
@@ -14,9 +13,6 @@
 import com.quickblox.sample.pushnotifications.java.utils.ActivityLifecycle;
 import com.quickblox.sample.pushnotifications.java.utils.ToastUtils;
 
-import io.fabric.sdk.android.Fabric;
-
-
 public class App extends Application {
     private static final String TAG = App.class.getSimpleName();
 
@@ -32,13 +28,11 @@ public class App extends Application {
     @Override
     public void onCreate() {
         super.onCreate();
-        Fabric.with(this, new Crashlytics());
         instance = this;
         ActivityLifecycle.init();
         checkConfig();
         initCredentials();
         initQBSessionManager();
-        initFabric();
         initPushManager();
     }
 
@@ -119,12 +113,6 @@ public void onSubscriptionDeleted(boolean success) {
         });
     }
 
-    private void initFabric() {
-        if (!BuildConfig.DEBUG) {
-            Fabric.with(this, new Crashlytics());
-        }
-    }
-
     public static synchronized App getInstance() {
         return instance;
     }
diff --git a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/AppInfoActivity.java b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/AppInfoActivity.java
index 70caf95fc..2efd23d8c 100644
--- a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/AppInfoActivity.java
+++ b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/AppInfoActivity.java
@@ -14,9 +14,7 @@
 import com.quickblox.sample.pushnotifications.java.BuildConfig;
 import com.quickblox.sample.pushnotifications.java.R;
 
-
 public class AppInfoActivity extends BaseActivity {
-
     private TextView appVersionTextView;
     private TextView sdkVersionTextView;
     private TextView appIDTextView;
diff --git a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/BaseActivity.java b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/BaseActivity.java
index c066c1ffe..bdf030ca4 100644
--- a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/BaseActivity.java
+++ b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/BaseActivity.java
@@ -9,16 +9,16 @@
 import android.view.View;
 import android.view.ViewConfiguration;
 
+import androidx.annotation.StringRes;
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AppCompatActivity;
+
 import com.quickblox.core.exception.QBResponseException;
 import com.quickblox.sample.pushnotifications.java.R;
 import com.quickblox.sample.pushnotifications.java.utils.ErrorUtils;
 
 import java.lang.reflect.Field;
 
-import androidx.annotation.StringRes;
-import androidx.appcompat.app.ActionBar;
-import androidx.appcompat.app.AppCompatActivity;
-
 public class BaseActivity extends AppCompatActivity {
     private static final String TAG = BaseActivity.class.getSimpleName();
     protected ActionBar actionBar;
diff --git a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/LoginActivity.java b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/LoginActivity.java
index b9c8f97d7..5f5591a01 100644
--- a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/LoginActivity.java
+++ b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/LoginActivity.java
@@ -66,7 +66,7 @@ public void onClick(View v) {
 
     @Override
     public void onBackPressed() {
-
+        // empty
     }
 
     private void signIn() {
diff --git a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/MessagesActivity.java b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/MessagesActivity.java
index 799f61350..be1551607 100644
--- a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/MessagesActivity.java
+++ b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/MessagesActivity.java
@@ -18,6 +18,8 @@
 import android.widget.ListView;
 import android.widget.ProgressBar;
 
+import androidx.localbroadcastmanager.content.LocalBroadcastManager;
+
 import com.quickblox.auth.session.QBSessionManager;
 import com.quickblox.auth.session.QBSettings;
 import com.quickblox.core.QBEntityCallback;
@@ -39,10 +41,7 @@
 import java.util.ArrayList;
 import java.util.List;
 
-import androidx.localbroadcastmanager.content.LocalBroadcastManager;
-
 public class MessagesActivity extends BaseActivity implements TextWatcher {
-
     private final String TAG = getClass().getSimpleName();
 
     private EditText outgoingMessageEditText;
@@ -175,11 +174,9 @@ private void sendPushMessage() {
             return;
         }
 
-        // Send Push: create QuickBlox Push Notification Event
         QBEvent qbEvent = new QBEvent();
         qbEvent.setNotificationType(QBNotificationType.PUSH);
         qbEvent.setEnvironment(QBEnvironment.DEVELOPMENT);
-        // Generic push - will be delivered to all platforms (Android, iOS, WP, Blackberry..)
         qbEvent.setMessage(outMessage);
 
         StringifyArrayList<Integer> userIds = new StringifyArrayList<>();
@@ -219,12 +216,12 @@ private boolean isValidData(String message) {
 
     @Override
     public void beforeTextChanged(CharSequence s, int start, int count, int after) {
-        //ignore
+        // empty
     }
 
     @Override
     public void onTextChanged(CharSequence s, int start, int before, int count) {
-        //ignore
+        // empty
     }
 
     @Override
@@ -239,12 +236,12 @@ private void unsubscribeFromPushes() {
             QBPushManager.getInstance().addListener(new QBPushManager.QBSubscribeListener() {
                 @Override
                 public void onSubscriptionCreated() {
-
+                    // empty
                 }
 
                 @Override
                 public void onSubscriptionError(Exception e, int i) {
-
+                    // empty
                 }
 
                 @Override
diff --git a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/SplashActivity.java b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/SplashActivity.java
index 620452323..5a486fcde 100644
--- a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/SplashActivity.java
+++ b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/activities/SplashActivity.java
@@ -4,17 +4,11 @@
 import android.content.pm.PackageManager;
 import android.os.Bundle;
 import android.os.Handler;
-import android.util.Log;
-import android.view.View;
 import android.widget.TextView;
 
-import com.quickblox.core.QBEntityCallback;
-import com.quickblox.core.exception.QBResponseException;
-import com.quickblox.sample.pushnotifications.java.App;
 import com.quickblox.sample.pushnotifications.java.R;
 import com.quickblox.sample.pushnotifications.java.utils.Consts;
 import com.quickblox.sample.pushnotifications.java.utils.SharedPrefsHelper;
-import com.quickblox.users.QBUsers;
 import com.quickblox.users.model.QBUser;
 
 public class SplashActivity extends BaseActivity {
@@ -72,6 +66,5 @@ public void run() {
                 }
             }, SPLASH_DELAY);
         }
-
     }
 }
\ No newline at end of file
diff --git a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ActivityLifecycle.java b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ActivityLifecycle.java
index fb247d87b..b7a9aeb64 100644
--- a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ActivityLifecycle.java
+++ b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ActivityLifecycle.java
@@ -7,7 +7,6 @@
 import com.quickblox.sample.pushnotifications.java.App;
 
 public class ActivityLifecycle implements Application.ActivityLifecycleCallbacks {
-
     private static ActivityLifecycle instance;
 
     private boolean foreground = false;
@@ -33,12 +32,12 @@ public boolean isBackground() {
 
     @Override
     public void onActivityCreated(Activity activity, Bundle savedInstanceState) {
-
+        // empty
     }
 
     @Override
     public void onActivityStarted(Activity activity) {
-
+        // empty
     }
 
     @Override
@@ -53,16 +52,16 @@ public void onActivityPaused(Activity activity) {
 
     @Override
     public void onActivityStopped(Activity activity) {
-
+        // empty
     }
 
     @Override
     public void onActivitySaveInstanceState(Activity activity, Bundle outState) {
-
+        // empty
     }
 
     @Override
     public void onActivityDestroyed(Activity activity) {
-
+        // empty
     }
 }
\ No newline at end of file
diff --git a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ErrorUtils.java b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ErrorUtils.java
index 71b01e2c0..f231c7a31 100644
--- a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ErrorUtils.java
+++ b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ErrorUtils.java
@@ -5,6 +5,9 @@
 import android.os.Looper;
 import android.view.View;
 
+import androidx.annotation.StringRes;
+import androidx.appcompat.app.AlertDialog;
+
 import com.google.android.material.snackbar.Snackbar;
 import com.quickblox.core.exception.QBResponseException;
 import com.quickblox.sample.pushnotifications.java.App;
@@ -12,11 +15,7 @@
 
 import java.util.List;
 
-import androidx.annotation.StringRes;
-import androidx.appcompat.app.AlertDialog;
-
 public class ErrorUtils {
-
     private static final String NO_CONNECTION_ERROR = App.getInstance().getString(R.string.error_connection_failed);
     private static final String NO_RESPONSE_TIMEOUT = App.getInstance().getString(R.string.error_no_responce_timeout);
     private static Handler mainThreadHandler = new Handler(Looper.getMainLooper());
diff --git a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/SharedPrefsHelper.java b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/SharedPrefsHelper.java
index 03252626a..b8428d395 100644
--- a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/SharedPrefsHelper.java
+++ b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/SharedPrefsHelper.java
@@ -9,7 +9,6 @@
 
 public class SharedPrefsHelper {
     private static final String SHARED_PREFS_NAME = "qb";
-
     private static final String QB_USER_ID = "qb_user_id";
     private static final String QB_USER_LOGIN = "qb_user_login";
     private static final String QB_USER_PASSWORD = "qb_user_password";
@@ -24,7 +23,6 @@ public static synchronized SharedPrefsHelper getInstance() {
         if (instance == null) {
             instance = new SharedPrefsHelper();
         }
-
         return instance;
     }
 
@@ -75,7 +73,6 @@ public boolean has(String key) {
         return sharedPreferences.contains(key);
     }
 
-
     public void saveQbUser(QBUser qbUser) {
         save(QB_USER_ID, qbUser.getId());
         save(QB_USER_LOGIN, qbUser.getLogin());
diff --git a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ToastUtils.java b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ToastUtils.java
index 5961a2839..97d4a80cb 100644
--- a/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ToastUtils.java
+++ b/sample-pushnotifications-java/app/src/main/java/com/quickblox/sample/pushnotifications/java/utils/ToastUtils.java
@@ -2,10 +2,10 @@
 
 import android.widget.Toast;
 
-import com.quickblox.sample.pushnotifications.java.App;
-
 import androidx.annotation.StringRes;
 
+import com.quickblox.sample.pushnotifications.java.App;
+
 public class ToastUtils {
 
     private ToastUtils() {
diff --git a/sample-pushnotifications-java/build.gradle b/sample-pushnotifications-java/build.gradle
index eafb6a784..66a974f42 100644
--- a/sample-pushnotifications-java/build.gradle
+++ b/sample-pushnotifications-java/build.gradle
@@ -1,22 +1,19 @@
 buildscript {
     repositories {
         google()
-        jcenter()
+        mavenCentral()
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.2.0'
-        classpath 'com.google.gms:google-services:4.1.0'
+        classpath 'com.android.tools.build:gradle:4.2.2'
+        classpath 'com.google.gms:google-services:4.3.10'
     }
 }
 
 allprojects {
     repositories {
         google()
-        jcenter()
-        maven {
-            url "https://github.com/QuickBlox/quickblox-android-sdk-releases/raw/master/"
-        }
+        mavenCentral()
     }
 }
 
@@ -25,20 +22,14 @@ ext {
     dimensionDefault = 'default'
 
     // QuickBlox SDK version
-    qbSdkVersion = '3.9.4'
+    qbSdkVersion = '3.9.16'
 
-    //Fabric
-    fabricToolsVersion = '1.27.0'
+    // Firebase
+    firebaseCoreVersion = '21.0.0'
 
-    //Firebase
-    firebaseCoreVersion = '16.0.8'
+    // Material
+    materialVersion = '1.6.0'
 
-    //Material
-    materialVersion = '1.0.0'
-
-    //RobotoTextView
+    // RobotoTextView
     robotoTextViewVersion = '4.0.0'
-
-    //Crashlytics
-    crashlyticsVersion = '2.9.5'
 }
\ No newline at end of file
diff --git a/sample-pushnotifications-java/gradle/wrapper/gradle-wrapper.properties b/sample-pushnotifications-java/gradle/wrapper/gradle-wrapper.properties
index 9a4163a4f..4d9ca1649 100644
--- a/sample-pushnotifications-java/gradle/wrapper/gradle-wrapper.properties
+++ b/sample-pushnotifications-java/gradle/wrapper/gradle-wrapper.properties
@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.7.1-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists